If you want to become a homeowner, you're going to need a good credit score, unless you have piles of cash lying around. For most, though, the credit score is the key to determining whether they will qualify for a mortgage loan.

Lenders want to see a high credit score — a numerical figure that encapsulates borrowers' past histories of managing their money and paying their bills on time — before they lend borrowers money. This is especially important now; Lenders were heavily criticized for passing out mortgage money too freely during the housing boom, something that led to the record number of foreclosures we're seeing today.

But how can you boost your own credit score before applying for a mortgage loan? The good news is that it's certainly possible. The bad news is that it takes time, and real effort. In short, you have to actively change your spending habits.

Home buyers with the highest credit scores qualify for the mortgage loans with the lowest interest rates. Buyers whose credit scores - also known as their FICO scores - are too low will either have to pay higher interest rates on their home loans or won't qualify for a mortgage at all.

If you want to improve your credit score, first order copies of your credit reports from the three national credit bureaus, Experian, Equifax and TransUnion. You can do this for free by visiting AnnualCreditReport.com, a Web site that all three bureaus own.

Study your reports and look for any errors. If you do find a mistake, write to the agencies to correct it. This can boost your credit score. Be warned, though, that this is a slow process. It's best to check your credit reports long before you want to take out a mortgage loan.

Your second step should be to eliminate your credit-card debt. Homebuyers with too much of this debt will hurt their credit score. And pay your bills on time. Homebuyers will have stronger credit scores if they already have a history of managing their money and payments responsibly. Mortgage lenders today don't like to lend money to borrowers who have shown signs of not paying their debts on time.

Finally, don't open new credit cards. Some potential home buyers do this before applying for a loan, thinking that it is important to increase their amount of available credit. But doing this may backfire and instead lower your credit scores.

You should be aware that there is no quick way to boost a credit score. Because of this, it may make sense for some consumers to wait a year or more before applying for a mortgage loan. They should just make sure they use this time wisely by paying down their debts and developing a history of paying their bills on time.